Online private car-hailing services have gained popularity in China. As cities across the country are expanding, public transport in many places hasn’t kept pace with increased demand.

Traffic conditions worsened in the Chinese capital in 2015 due to plunging oil prices and the car-hailing services, Zhou Zhengyu, director of the Beijing Municipal Commission of Transportation, said at the fourth plenary session of the municipal People’s Congress on Monday.

Zhou Zhengyu, director of the Beijing Municipal Commission of Transportation

According to Mr. Zhou, there are more than 100,000 private cars involved in online car-hailing services in the city, fulfilling 600,000 to 700,000 peer-to-peer ride orders each day and thus “exacerbating road congestion.”

Online private car-hailing services have gained popularity in China. As cities across the country are expanding, public transport in many places hasn’t kept pace with increased demand. On top of that, more and more cities have sought to curb air pollution and congestion by making it increasingly tough to own a set of wheels.

Mr. Zhou’s comments are drawing a barrage of criticism online.

“Do you offer us sufficient public transport measures?” asked one user on China’s Weibo microblogging platform.

“Why don’t you say too many auto makers produce too many cars?” wrote another user.

China is the world’s largest market for new cars, ahead of the U.S., with more than 21 million passenger vehicles sold here last year. The government-backed China Association of Automobile Manufacturers predicted new-car sales would grow 7.8% this year to 22.76 million vehicles.